Diabetes is a disease in which the body has impaired ability to use and store glucose. This results in abnormally high levels of glucose in the bloodstream. High glucose levels may damage the delicate cells of the retinal capillaries. Sometimes the capillaries become occluded and the retina is deprived of oxygen. In some eyes the vessels walls become leaky and fluid seeps into the retinal tissue. Diabetic retinopathy is classified as non-proliferative (NPDR) and proliferative (PDR). In patients with proliferative diabetic retinopathy oxygen deprivation triggers the production of growth factors that stimulate abnormal blood vessel growth. The abnormal blood vessels are called neovascularization. Neovascularization does not supply the retina with oxygen. Instead it grows up from the surface of the retina or optic nerve into the vitreous of the eye or on the iris. These vessels are very fragile and frequently cause hemorrhage inside the vitreous gel of the eye. Even without neovascularization, the vessels may leak into the retina causing swelling and an accumulation of blood products within the retina.
Both NPDR and PDR are diagnosed on dilated examination of the retina. Diabetic retinopathy is usually treated with laser and medications. This is not possible when there is dense and persistent vitreous hemorrhage in the eye. These eyes are treated with vitrectomy surgery. This technique allows the doctor to clean away the vitreous blood and apply laser to prevent future bleeding.
This is the first and earliest stage of diabetic retinopathy. NPDR occurs when the small blood vessels of the retina start to leak fluid or bleed. This activity will lead to the formation of deposits called exudates. Once these blood vessels start to leak swelling within the central part of the retina occurs. When the leakage of these blood vessels causes swelling, macular edema sets in and the blood vessels can become blocked. This stage of diabetic retinopathy is common when a person develops diabetes. Most diabetics have some grade of NPDR. It is imperative to maintain regular eye examinations with the retina specialists at Regional Retinal Consultants to monitor and treat NPDR.
When new vessels start to grow as a result of the existing vessels becoming blocked, this marks the beginning of the next stage of diabetic retinopathy, proliferative diabetic retinopathy. This level of diabetic retinopathy is the most severe and dangerous for the diabetic patient. These new abnormal blood vessels can grow on the retina, optic nerve, iris or into the vitreous gel inside the eye, and tend to grow poorly and are very fragile. The damage that these blood vessels bring to retina can be catastrophic and include hemorrhages on the retina, scar tissues build up, and possible retina detachment.
Diabetic Retinopathy Symptoms
- If you are a diabetic patient it is suggested by the RRC that you have regular eye exams to look for symptoms. Diabetic retinopathy does not really have any initial warning signs.
- Retinal swelling may cause blurred vision and distortion.
- Objects may look smaller or larger than normal
- Floaters may appear due to the bleeding of the blood vessels.
*If proliferative diabetic retinopathy is left untreated blindness can occur. The best alternative to fighting PDR is early detection so that you and your eye doctor can begin to control this development.
How is diabetic retinopathy diagnosed?
Retinopathy, particularly at its earliest stages may not produce any visual symptoms. Early detection is the best way to prevent vision loss. Therefore, it is crucial for all patients with diabetes to undergo a complete eye exam by an ophthalmologist, with careful evaluation of the retina at least once a year and more frequently once diabetic retinopathy is detected.
How is diabetic retinopathy treated?
Treatment depends primarily upon the type and severity of the retinopathy. The most important aspect of treatment, however, is prevention. By regularly monitoring blood sugar, and maintaining a healthy program of diet and exercise, you can significantly reduce your chances of developing retinopathy.
Laser is performed by directing a beam of light into the eye to treat the damaged parts of the retina. In cases of background diabetic retinopathy with macular edema, the laser is used to seal off leaking blood vessels and to stimulate the eye to reabsorb the fluid. When abnormal blood vessel growth is present, as in proliferative diabetic retinopathy, laser is used to decrease and prevent blood vessel growth. Laser surgery is often performed in the office and usually only requires topical or local anesthesia. Multiple laser treatments are often necessary.
Bleeding into the vitreous cavity can occur in severe cases of proliferative diabetic retinopathy. If the vitreous is filled with blood, surgery may be recommended to remove the blood from the center of the eye and the abnormal vessels causing the bleeding. Even though the blood may be severely impairing your vision, your doctor may advise waiting to see if the blood clears on its own before recommending surgery. Vitrectomy surgery is also performed to repair retinal detachments caused by excessive scar tissue that develops in proliferative retinopathy.